Question: Solve for $d$. $4d-4=5d-8$ $d=$
Explanation: We need to manipulate the equation to get $ d $ by itself. $\begin{aligned} 4d-4&=5d-8 \\\\ 4d-4 {-5d} &= 5d-8{-5d} &&\gray{\text{Subtract 5d from each side.}}\\\\ -1d-4&=-8 &&\gray{\text{Combine like terms.}}\\\\ -1d-4{+4} &= -8{+4} &&\gray{\text{Add 4 to each side.}}\\\\ -1d &=-4 &&\gray{\text{Combine like terms.}}\\\\ \dfrac{-1d}{{-1}} &= \dfrac{-4}{{-1}} &&\gray{\text{Divide each side by -1.}}\\\\ d &= {4} &&\gray{\text{Simplify.}}\\\\ \end{aligned}$ The answer: $ d= { 4 }~~~~~~~~$ [Let's check our work!]